Assessment of the Benefits of Targeted Interventions for Pandemic Control in China Based on Machine Learning Method and Web Service for COVID-19 Policy Simulation

Taking the Chinese city of Xiamen as an example,simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019(COVID-19)and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures.A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios.The comparison was conducted between simulated and real cases in Xiamen.A web interface with adjustable parameters,including choice of intervention measures,intervention weights,vaccination,and viral variants,was designed for users to run the simulation.The total case number was set as the outcome.The cumulative number was 4,614,641 without restrictions and 78 under the strictest intervention set.Simulation with the parameters closest to the real situation of the Xiamen outbreak was performed to verify the accuracy and reliability of the model.The simulation model generated a duration of 52 days before the daily cases dropped to zero and the final cumulative case number of 200,which were 25 more days and 36 fewer cases than the real situation,respectively.Targeted interventions could benefit the prevention and control of COVID-19 outbreak while safeguarding public health and mitigating impacts on people’s livelihood.

China＇s Macroeconomic Outlook and Risk Assessment： Counterfactual Analysis, Policy Simulation, and Long-Term Governance- A Summary of Annual Report （2015-2016）

Abstract This summary report highlights the confluence of continued downward pressures and deflation scares in the face of looming uncertainty in China＇s key macroeconomic landscapes. Counterfactual analyses and policy simulations are conducted, in addition to benchmark forecasts, based on IAR-CMM model and taking into account both cyclical and secular factors. Economic deceleration is projected to continue in the short to medium term, with real GDP growth declining to 6.3% （5.5% using more reliable instead of official data） in 2016 and facing a significant risk of sliding further down in 2017. Five key factors contributing to the weak outlook, additional to frictions and impediments associated with economic transition/restructuring and lackluster domestic/external demands, are identified, including： lack of new growth/ development engine, exhaustion of government-led driving force, the crowding-out of private sectors by state-owned enterprises （SOEs） with excess capacity／capital overhang, nonperforming government sectors and officials, and twist or misinterpretation of the ＂New Normal.＂ A root cause of these problems, lying with sluggishness in China＇s transformation into a market based economy, has to do with overpowered government but underpowered market in resource allocation and government underperformance in enforcing integrity and transparency in the marketplace and in providing public goods and services. At the nexus between inclusive growth and institutional transformation are market oriented and rule of law governed structural reforms and harmonious development. As such, fundamental institutional reforms that dialectically balance demand and supply side factors and properly weigh short run stabilization against long run development should be elevated to the top of the agenda.

Conquering China＇s Unbalanced and Inadequate Development： Macroeconomic Outlook, Policy Simulations, and Reform Implementation--A Summary of Annual SUFE Macroeconomic Report （2017-2018）

Leaving year 2017 China＇s macroeconomy is continuously characterized by unbalanced and inadequate development. Whereas some aggregate indicators have shown improvement over the year, the cumulative growth rates in consumption and fixed asset investment have continued theirdownward trajectories. Worsening income inequality and resource misallocations, both between secondary and tertiary industries, and within the latter, pose serious challenges, let alone the systemic risk associated with the flourishing shadow banking system, rapid credit growth and debt overhang that weigh on the Chinese economy like the Sword of Damocles. This summary report highlights both the status quo and the consequences of the unbalanced and inadequate development embodied in China＇s persistently distorted economic structure, and the role of deepening reforms of the institutions and governance in resolving the problems. Our analyses based on IAR-CMM model provide a unified framework for addressing China＇s short-, medium-, and long-term issues ir~ an internally coherent manner. Looking into year 2018, our benchmark projection of real GDP growth rate is 6.7% （6.41% using more reliable rather than the official data）. Alternative scenario analyses and policy simulations are conducted to reflect various aspects of the economic challenges in the short to long runs. Through the lens of these analyses we conclude that rule-of-law based and market-oriented structural reforms should continue to hold a center stage in China＇s transition from a phase of high-speed but unbalanced growth, to a stage of balanced and adequate high-quality development.

Monetary Policy Effects and Output Growth in Malawi: Using a Small Macroeconometric Model

This study tries to develop and use a small macroeconometric model to capture the main short-term macro dynamics and to forecast major macroeconomic variables of the Malawian economy. The results show that a reduction in the policy rate leads to a fall in the lending rate, but with an increase in money supply, and with an insignificant impact on output growth. The results suggest that monetary authorities in Malawi have to make a choice between the objectives of maintaining lower money supply and lowering the lending rate. The results also suggest that, despite the Reserve Bank of Malawi Act of 1989 stipulating that monetary authorities should pursue both price and high growth and employment objectives, our results reveal that price stability is the principal objective of monetary policy in the country. Suggesting that monetary authorities in the country should not only place more emphasis on the objective of stabilization and achieving low inflation, but also focus on supporting strong, sustained and shared growth. To some extent further suggesting that emphasis should be placed on policies and strategies aimed at structurally transforming the Malawian economy so that the monetary policies’ impact should translate into an increase in the country’s output and growth. Further suggesting enhanced effective coordination between fiscal and monetary policies.

Multi-agent system simulation for urban policy design:open space land use change problem

Multi-agent system(MAS)models have been increasingly applied to the simulation of complex phenomena in different areas,providing successful and credible results.Citizens behavior related to a specific urban activity(i.e.,recreation activities in a park,using bicycle for mobility purposes)can be modeled as an agent(actor)with several affinities and preferences which are dependent on aspects that affect the activity.A particular application of a MAS approach is in area of urban policy design,in which policies should be designed considering citizens needs,preferences and behavior.Once an open space in a city is available(i.e.,an industry is moved to an industrial area),a land use policy should contribute to identify the new use for the urban space.There are different land use policies that can be applied depending on which services or facilities must be empowered in the city.It is important to identify the correct policy in order to satisfy present citizens needs but considering also the future needs in a social changing context.A socio-technological simulation model has been developed to allow citizens to get a better understanding of the urban problem,its dynamics and explore the sustainability of the different solutions.,enhancing citizens to participate in the urban decisions through new technologies(i.e.,e-participation).This paper illustrates an open space MAS simulation model for land use design policies in which citizens can check their opinion and get a better understanding of the different choices and its acceptability by the community considering not only present neighborhood profiles,but also future neighborhood configurations.It is the first step before the development of the final software including a user friendly interface to let citizens with different cultural profiles to perform simulations as an essential and neutral tool to reach consensus during the decision-making process in urban policy design.

Beijing Urban Development Model:Urban Growth Analysis and Simulation

Urban growth analysis and simulation have been recently conducted by cellular automata （CA） models based on self-organizing theory which differs from system dynamics models. This paper describes the Beijing urban development model （BUDEM） which adopts the CA approach to support urban planning and policy evaluation. BUDEM, as a spatio-temporal dynamic model for simulating urban growth in the Beijing metropolitan area, is based on the urban growth theory and integrates logistic regression and MonoLoop to obtain the weights for the transition rule with multi-criteria evaluation configuration. Local sensitivity analysis for all the parameters of BUDEM is also carried out to assess the model＇s performances. The model is used to identify urban growth mechanisms in the various historical phases since 1986, to retrieve urban growth policies needed to implement the desired （planned） urban form in 2020, and to simulate urban growth scenarios until 2049 based on the urban form and parameter set in 2020. The model has been proved to be capable of analyzing historical urban growth mechanisms and predicting future urban growth for metropolitan areas in China.

From“selective two-child policy”to universal two-child policy:Will the payment crisis of China’s pension system be solved?

With the rapid population aging,the payment crisis of China’s pension insurance fund is increasing yearly.The government adjusts fertility policy to alleviate population aging and improve the solvency of pension insurance fund.On January1,2016,China’s fertility policy was adjusted from“selective two-child policy”to universal two-child policy.This paper establishes actuarial models to analyze how fertility policy adjustment influences the pension insurance fund and concludes as follows:(1)if the“one-child policy”were still employed,the accumulated deficit of pension insurance fund would appear in the year of 2076;(2)if all couples that satisfy the rules of“selective two-child policy”bear the second child,the time of accumulated deficit of pension insurance fund would be postponed by about 9 years;(3)after implementing universal two-child policy,the time of accumulated deficit of pension insurance fund would delay under different situations of fertility intentions,if more than 54% of the qualified couples bear a second child,the accumulated deficit of pension insurance fund would not appear before 2090.The above conclusions have passed the sensitivity tests.Therefore,“two-child policy”can alleviate the payment pressure of pension insurance fund.If the government wants to solve the payment crisis of pension insurance fund,fertility intentions should be improved.

Chinese Economy under the New"Dual Circulation"Strategy:Challenges and Opportunities-A Summary of the Annual SUFE Macroeconomic Report(2020-2021)

Entering year 2020,the Chinese economy was struck by the COVID-19 outbreak.The unprecedented pandemic,entangled with the already elevated complexities in the nation's internal environment and external surroundings,aggravated its economic outlook.Internal factors including severe education mismatch in China's labor force,its vanishing demographic dividend,the declined purchasing power of its middle-income groups,risen leverage ratio of households and enterprises,and soared local government debt reinforced to weaken China's domestic demand.External factors,especially uncertainty in the China-US relation in the face of the re-shaping global value chain,dragged world economic recovery and thus China's exports and imports.This summary report highlights some major challenges and opportunities faced by the nation under its new development strategy that stresses internal circulation of domestic economy aided by its interaction with the globe.Our analyses based on IAR-CMM model provide a unified framework for addressing China's short-,medium-,and long-term issues in an internally coherent manner.Looking into year 2021,our benchmark projection reports an 8.4%annual real GDP growth rate.Alternative scenario analyses and policy simulations are conducted to assess the impacts of potential downside risks and the corresponding policy options for ensuring implicit targets.Through the lens of these analyses,we conclude that a refocus on effective management of internal demand,while deepening structural reforms on supply side and advancing orderly opening up,can help smooth the internal and external circulations of the Chinese economy to achieve high-quality development.